The latest research shows that they can also distinguish between happy and angry facial expressions, and even show jealousy. And new experiments show they can even tell whether someone is trustworthy.
Once a dog deems someone untrustworthy, it will stop following the clues provided by that person. It is known that when someone points at something, dogs can understand the meaning behind it. If a dog's owner points to where the ball, stick, or food is, the dog will dart over and see where the owner is pointing.
New research shows that they can also quickly figure out whether people's gestures are misleading. A team led by Akiko Takaoka of Kyoto University in Japan published a paper in the journal Animal Cognition describing the responses of 34 dogs in a three-round instruction experiment.
In the first round of experiments, the researchers pointed to a container with food hidden inside.
But in the second round of experiments, they pointed to the empty container. In a third round of experiments, the same researchers again pointed to the container containing food.
But this time, the dog did not respond to the cues provided by the experimenter. Takaoka believes this shows that dogs can use their own experience to evaluate whether researchers are giving reliable instructions.
After three rounds of experiments, a new researcher repeated the first round of experiments. This time, the dog followed his clues with interest. Takaoka said she was surprised that a dog could "lower trust in a person" in such a short period of time.
Dogs have far more social intelligence than we imagine. This kind of social intelligence has been selectively evolved through long-term interactions with humans.
The next step, she added, is testing on closely related species such as wolves. This could reveal the "profound impact" domestication has on dogs' social intelligence.
The research shows that dogs like things that are predictable, said John Bradshaw of the University of Bristol in the UK. Whenever something in life becomes irregular, they will choose something else. He added that if they can't figure out what's coming next, they can become nervous, aggressive or fearful.
If the dog owner is erratic, the dog will often become behaviorally disordered. The last part of this experiment can be explained by dogs' enthusiasm for all kinds of new things: dogs have always been information dealers.
So they consider the new researchers "credible," Bradshaw said. For dog owner Victoria Standen, the research is not unexpected.
She has a Scottish Shepherd, a dog with extremely high intelligence. When out for a walk, her dog would sit at an intersection and wait for its owner to choose a direction. I would point in a direction and she would look in that direction and then go backHe looked at me to make sure it was in that direction.
Also, her dog is less likely to trust a stranger if his trustworthiness is disproven. Bradshaw said there is growing evidence that dogs are smarter than we think, but their IQs are very different from ours.
Dogs are very sensitive to human behavior, but they are far less biased.
They live in the present, he said, and do not reflect the past or plan for the future in an abstract way. He added that when dogs enter an environment, they only think about what's there and don't think deeply about the possible consequences.
Dognition chief scientist Brian Hare said the study is further evidence that dogs don’t blindly follow our gestures. They evaluate the information we provide based in part on how reliable it is in helping them complete their tasks.
For example, the family dog ​​will tend to ignore these clues when you point the wrong way and directly use its own memory to find the hidden object.